Question

Estimate a retardation factor for the transport of dissolved chloroform (CHCl3) under the following conditions:

a. In the saturated zone, where n = 0.3, foc = 1%, and soil bulk density =2.1 g/cm3

Answer 1

Retardation Factor R = 1 + rbkd /q

rb = bulk density = rs(1-q)

rs = solids density

q = porosity

kd = (soil) distribution coefficient = foc Koc

foc = fraction organic carbon

Koc = organic carbon/water partition coefficient

= 1 + 2.1(0.1)/0.3

1 + 0.7

= 1.7